INESC Porto, Porto, Portugal.
Opt Lett. 2013 Aug 1;38(15):2927-9. doi: 10.1364/OL.38.002927.
An intensity-based highly birefringent (Hi-Bi) fiber loop mirror (FLM) sensor is proposed which uses a wavelength-division multiplexing (WDM) fiber coupler. The effect of integrating the WDM coupler in a FLM configuration is first studied. A section of Hi-Bi (bow-tie) fiber of length 0.26 m is then placed in the fiber loop, making the spectral response of the device simultaneously dependent on the Hi-Bi fiber section and WDM coupler characteristics. When strain is applied to the sensing head, the spectral signal is modulated in amplitude, in contrast with the conventional Hi-Bi FLM sensors in which there are wavelength shifts. The sensor was characterized in strain and a sensitivity of (-2.2±0.4)×10(-3) με(-1) for a range of 300 με was attained. The self-referenced character of the sensor is noted.
提出了一种基于强度的高双折射（Hi-Bi）光纤环镜（FLM）传感器，该传感器使用了波分复用（WDM）光纤耦合器。首先研究了在 FLM 配置中集成 WDM 耦合器的效果。然后，将长度为 0.26 m 的一段 Hi-Bi（蝴蝶结）光纤放置在光纤环中，使得器件的光谱响应同时取决于 Hi-Bi 光纤部分和 WDM 耦合器的特性。当应变施加到传感头时，光谱信号的幅度会发生调制，而在传统的 Hi-Bi FLM 传感器中，只有波长发生了移动。对传感器进行了应变特性的表征，在 300 με 的范围内，获得了（-2.2±0.4）×10(-3) με(-1)的灵敏度。还注意到了传感器的自参考特性。
